April Journal Round-Up

Welcome to the April journal round-up! After the vascular-heavy blog last month, we’ve got a much more even mix this week with a lot of interesting articles to cover. As ever, let me know if you think anything is missing!

Emergency – Although the CTA spot sign is validated for predicting expansion of intracranial haemorrhage, given that many presenting with a haemorrhage do not get a CTA, prediction on the basis of non contrast CT alone would be useful. Morotti et al. aim to do just this in Stroke, developing a scoring system which they validate in two trial cohorts. Their 5-point scoring system has three components: the ‘blend sign’, intrahaematoma hypodensity, and time from onset, and showed good correlation with haematoma expansion.

In Emergency Radiology this month, Bhattacharya and Pendarkhar present a pictorial review of neurovascular emergencies in pregnancy and the puerperium, which acts as a helpful aide-memoire when assessing patients presenting in these periods.

Tumour – As previously discussed on this blog (see the July and November Tumour sections), it will become increasingly important to become familiar with imaging phenotypes of specific gene mutations in the assessment of brain tumours after the 2016 WHO classification. Lasocki et al. have conducted a useful study examining the specific imaging manifestations of 1p/19q codeletion grade II/III gliomas on structural MRI. They found that the presentation of >50% T2/FLAIR mismatch had the highest sensitivity and specificity for non-codeleted tumours, and calcification for codeleted tumours. Whilst these features were not universal, they suggest that in situations where genotyping is not possible they could be used as a surrogate marker.

Infection/Inflammatory – Two articles this month tackle the often tricky clinicoradiological issue of progressive multifocal leukoencephalopathy (PML). A review in Lancet Neurology by Morgan et al. goes into detail about what we have learned about the pathophysiology of the disease, the role of MRI in diagnosis in monitoring and future directions and challenges, providing a broad clinical context for the specific role of imaging. Wattjes et al. in JNNP focus on the imaging findings in the more inflammatory form of PML seen in natalizumab treatment and the phenotypic overlaps with PML-IRIS.

CJD can be a difficult diagnosis to make due to its rarity in the general neurology clinic, and Rudge et al. examine a cohort of patients from a specialist prion clinic in order to determine the most useful diagnostic features, confirming the importance of acquiring DWI and cautioning the interpretation of CSF 14-3-3 protein which is helpful but nonspecific.

Spine – The differential for transverse myelitis is wide, and Chee et al. help to narrow it with a study looking at the specific imaging features pointing towards an aquaporin-4 positive neuromyelitis optica related transverse myelitis, suggesting a scoring system including cervicomedullary involvement, high expansion ratio and bright spotty lesions.

Uei et al. in Spine tackled the bane of the on-call neuroradiologist, the cord compression MRI, and find that the degree of radiological cord compression (as measured by the epidural spinal cord compression scale) does not correlate well with the degree of clinical paralysis. They suggest that the degree of anterolateral or circumferential compression is more important than the ESCC grade, particularly in the cervical spine, in predicting rapidly progressive paralysis. This is an interesting paper, providing a surgical perspective for a very frequent radiological presentation.

Paediatric – With the ongoing concern regarding the retention of gadolinium, Dunger et al. present a timely and important study in Pediatric Radiology examining the utility of contrast administration in children with normal pre-contrast MRI brain examination (in over 3000 patients), finding that there are rarely any additional relevant findings from post contrast studies. This provides a powerful argument for restricting the use of gadolinium in this context.

Sanz et al. in BJR examined a cohort of paediatric patients with septic shock to determine the imaging findings in this clinical context, showing that ischaemia and cerebritis were the most common imaging presentations and suggesting that injury via vascular mechanisms is likely to be more clinically important than direct infective spread to the brain.

Miscellaneous – The incidental pituitary lesion is a common imaging finding but guidance as to appropriate imaging follow-up is often lacking. The ACR Incidental Findings committee have taken on this issue and in an article in JACR by Hoang et al. provide useful flowcharts for incidental lesions seen on CT or MRI and PET – which might be useful to have stuck on the reporting room wall!

Finally, a welcome intervention to all those disappointed by the suboptimal neuroanatomy knowledge displayed by the antagonist in the most recent James Bond film, SPECTRE, as Dr Currie recommends himself to would-be Bond villains as a consulting neuroradiologist in a fantastic letter to Neuroradiology.

That’s all for this week – but I’d be particularly keen to hear about any other fictional neuroanatomy blunders that Dr Currie could sort out for us…

March Journal Round-Up

Welcome to the March journal round-up!

Trauma – Blunt cerebrovascular injury presents a significant clinical and radiological problem, as it can be very difficult to detect but screening all patients risks overutilization of limited resources and potential overdiagnosis. Two articles this month tackle this issue – a concise review by Nagpal et al. in AJNR compares the available diagnostic criteria and grading scales, whilst Rutman et al. in Radiographics provide a more comprehensive pictorial review with a focus on explaining the underlying pathophysiology.

Another common pathology associated with blunt trauma, thoracolumbar spine injury, is the subject of a review by Bonfante et al. in Neurographics, who discuss the pathology and biomechanics of injury to this region, compare the available classification systems for the injuries and discuss the clinical utility of these systems. This is a useful reference for anyone reporting trauma studies.

Vascular Last month we included the ASNR’s guidance on vessel wall imaging. This month Pinho et al. in Neurographics give us a practical guide to vessel wall imaging, covering technical guidance on optimising imaging protocols and normal and abnormal findings. Potential expanded roles for vessel wall imaging are covered in two further articles this month – Dlamini et al. examine the application in paediatric stroke, and Lehman et al. in JNS review its use in aneurysm imaging (table 1 is an excellent reference guide to the findings in different types of aneurysm).

With the increasing use of T2* and susceptibility weighted imaging as well as higher field strengths, microhaemorrhages are being detected with greater frequency and it can be difficult to determine their significance. Haller et al. in Radiology provide a clear and relevant review that covers their detection, radiological-pathological correlation and their significance to multiple disease processes, as well as normal ageing.

Intervention – Two studies this month provided further evidence for the potential to extend the role of mechanical thrombectomy beyond large vessel occlusion within 6 hours of symptom onset. Following encouraging evidence from prospective trials, a retrospective study by Bucke et al. looked at the outcomes of patients with wake up strokes and strokes of uncertain daytime onset time in comparison to their ‘control’ cohort of within-time mechanical thrombectomy, and showed equivalence of the outcomes of the wake-up stroke cohort with controls and also a benefit related to the use of advanced imaging (i.e. MRI and CT perfusion). Haussen et al. used two prospective registries to compare mechanical thrombectomy with medical treatment alone in patients with mild symptoms (NIHSS </=5), and demonstrated a benefit in discharge NIHSS for mechanical thrombectomy.

Inflammatory – A review in Nature Reviews Neurology by Geraldes et al. should be required reading for neuroradiology trainees – the MAGNIMS study group reconvened to update their ‘red flags’, radiological signs that should alert the radiologist against a diagnosis of multiple sclerosis in the presence of white matter lesions. Given the prevalence of nonspecific white matter lesions in neuroradiology practice, this remains a frequent problem and their mnemonic ‘MIMICS’ is valuable to remember pointers towards other causes.

One aspect the authors of the above review touch upon is the central vein sign (veins running within the centre of white matter lesions), a presumed biomarker to distinguish MS from other causes of white matter lesions, which has been around for a while but has gained traction more recently with a publication by NAIMS on its evolution and use in 2016. An editorial in Neurology this week by Miller suggests this sign is ready for clinical use, expanding on an article by Cortese et al. demonstrating the sign’s value in distinguishing between MS and NMO spectrum disorders.

Paediatric – An article in AJR by Orru et al. provides a simple and effective approach to the assessment of the child with macrocephaly, with suggested imaging protocols and a pictorial review of common and less common causes.

Miscellaneous – Finally, a fascinating article by Reicher et al. in BJR examines the working practice of UK neuroradiologists and asks what we can learn from the aviation industry, specifically air traffic controllers who perform a qualitatively similar job, and cognitive science about how to improve it. The discrepancy between working practices as described by surveys conducted of the two professions and its potential impact on performance makes for thought-provoking reading!

That’s all for this month. As ever, let us know if there’s anything important we’ve missed, and have a good month!

February Journal Round-Up

Welcome to the February journal round-up!

Vascular – It’s a bit stroke-heavy this month, so a good place to start is the new American Heart Association stroke guidelines, published in Stroke. Although you may not want to read all 345 pages, the short sections on imaging and thrombectomy are a useful summary of the level of evidence for various factors that will affect us as radiologists, and are worth a read.

As a useful adjunct to this for neurointerventionalists, the Society of Neurointerventional Surgeons have also published updated guidance on mechanical thrombectomy, focusing on the evidence base for specific technical aspects of the procedure, in JNIS.

And for a more detailed discussion of the specific imaging modalities and their strengths and weaknesses in imaging evaluation of stroke, Smith and Rowland Hill have also provided a comprehensive review in the BJR.

Evaluation of carotid disease is clearly a crucial part of stroke imaging, and the relatively new technique of vessel wall imaging is an exciting prospect for this application. The ASNR have published a white paper with their recommendations for the use of vessel wall imaging, which provides an excellent context for where it can be most clinically useful.

Dural arteriovenous fistulae are notoriously difficult to diagnose, and in AJNR this month Copelan et al. describe a case series for a particular characteristic appearance of medullary oedema and enhancement in Cognard type V fistulae, noting the importance of recognising these features to avoid a long work-up for alternative pathologies.

Neoplastic – After the discussion of machine learning techniques in neuroradiology last month, the discussion in AJNR now focuses down on to its use in brain tumours in the new field of ‘radiomics’, noting the particular utility in neuro-oncology because of the potential to align imaging and genetic findings.

Inflammatory – Antibody-mediated encephalitides are increasingly understood to be much more common than we thought – indeed the most common, anti-NMDAR encephalitis, is more common than herpes encephalitis in young people. Yet this can seem like a bewildering array of random letters to the uninitiated! An excellent review in NEJM gives clinical context and highlights useful imaging findings to provide an introduction to these important pathologies.

Erdheim-Chester disease is a rare non-Langerhans cell histiocytosis, and Parks et al. in Neurology Clinical Practice use their relatively large cohort of 53 patients to examine the neuroradiological features of this disease.

Spine – The journal Neurosurgery have a useful (and open access) neuroradiology review series, and I have highlighted two articles from the series in this month’s blog. The first, by Chokshi et al., examines spinal neoplasms (both vertebral and cord) and also provides a very useful post-treatment section, particularly the imaging appearances of radiation-related complications.

Miscellaneous – Epilepsy imaging is an extremely challenging area for neuroradiology trainees, and there is a helpful review in Current Opinion in Neurology by Ruber et al. which focuses on accurate protocolling and the roles of advanced imaging for presurgical planning, as well as looking to potential future applications.

The second Neurosurgery neuroradiology review article, by Hudgins & Baugnon, concerns the skull base and provides an excellent overview and pictorial review of the anatomy and pathology of this complex region.

That’s all for this month. Hope you found it helpful, and do let us know if we’ve missed anything!

January Journal Round-Up

Welcome to the January journal round-up! Before we begin, we are pleased to announce the BSNR Trainee Study Days will be held in Newcastle on May 10-11th, with a focus on paediatric and spinal imaging and a mixture of lectures and workshops, modeled on the successful pre-annual meeting trainee days. Please email bsnr.traineeday@gmail.com to register your interest or for more information.

Vascular/Intervention – There is more support for extended (>6 hours) thrombectomy for proximal anterior circulation occlusions with the publication by Albers et al. in NEJM of results from the DEFUSE 3 trial. Using CT or MR perfusion and an automated imaging postprocessing system to select patients, they showed in an RCT that intervention following medical therapy up to 16 hours still conferred benefit.

Jansen et al. in Radiology went looking for other imaging correlates of response to intra-arterial therapy. They retrospectively used MR CLEAN trial data to examine whether a score based on the degree of cortical vein opacification (‘COVES’) on CT angiography could predict outcome, showing a higher mortality and no shift towards better functional outcome following intra-arterial treatment in those with a COVES (calculated looking at the superficial middle cerebral vein, vein of Labbe and the sphenoparietal sinus) of more than 0.

Neoplastic – In Practical Neurology, Larsen et al. give a timely overview of the role of imaging in the diagnosis, treatment planning and monitoring of low-grade glioma, in view of the trend towards more aggressive treatment and the changes in the 2016 WHO classification.

Leaning more towards treatment, Patibandla et al. have summarised the applications of stereotactic radiosurgery to help the neuroradiologist in the neuro-oncology MDT, with a pragmatic approach to the imaging aspects of common usages.

Inflammatory – It was all about multiple sclerosis (MS) this month, with the updated McDonald criteria published in the Lancet Neurology – key changes including the demonstration of CSF oligoclonal bands, the admissibility of symptomatic lesions in determination of dissemination in space or time, and the inclusion of cortical lesions with juxtacortical lesions. And just in the nick of time, as in the same journal a retrospective study by Filippi et al demonstrated equivalence of the 2010 McDonald criteria with the 2016 MAGNIMS criteria in predicting progression from clinically isolated syndrome, but highlighted possible areas for future development (at least one of which, the symptomatic lesions, has been incorporated into the new McDonald guidelines).

An appropriately timed overview of the current state of knowledge in MS is provided by Reich et al. in NEJM, and although the imaging aspect is limited this is a valuable and clear summary of our understanding of the complex pathophysiology of this still poorly understood disease.

A major set of differential diagnoses of MS are NMO (neuromyelitis optica)-spectrum disorders, and fortunately Garbugio Dutra et al. have published an excellent review of the history, diagnostic criteria, imaging features and differentials for these diseases.

Away from demyelination, IgG4-related disease is an increasingly diagnosed systemic disorder and its central and peripheral nervous system manifestations are outlined in a useful review by AbdelRazek et al. As it can mimic a number of other conditions, the detailed knowledge of the clinical context and systemic manifestations provided is crucial and the imaging features are also helpfully outlined.

Degenerative – Two interesting articles this month examined the diagnostic criteria for cerebral amyloid angiopathy (CAA), increasingly recognised and important in older populations (see the August round-up for more clinical context). In Stroke, Greenberg and Charidimou examine the evolution and validation of the most commonly used diagnostic criteria, the Boston criteria, and look at future directions for its development.

Conversely, Rodrigues et al. in Lancet Neurology set out to develop criteria to determine CAA as the cause for intracranial lobar haemorrhage on CT (the Edinburgh CT criteria), and found that two imaging findings, concurrent subarachnoid haemorrhage and ‘finger-like projections’ from parenchymal haemorrhage, in combination with APOE4 allele possession, had high specificity for CAA. The accompanying comment by Werring points out the need to compare these two sets of criteria and the potential strengths of both.

Paediatric – Neuroimaging is critical in the evaluation of paediatric traumatic brain injury, and a review by Mendoza et al. in Neurographics provides a useful summary of the spectrum of findings in accidental TBI, particularly paediatric-specific patterns of injury, and the emerging uses of advanced imaging in this context. In Emergency Radiology, Tang et al. examine the emergency vascular conditions seen in paediatric populations, with a focus on the importance of recognising stroke mimics.

Miscellaneous – Treatment effects are often a difficult or forgotten area and so a comprehensive review of treatment-related CNS abnormalities by Lincoln et al. in BJR is very welcome, covering the spectrum of side effects including PRES, IRIS, radiation and newer biologic agents and their specific complications.

And finally, we are constantly threatened with obliteration as radiologists by artificial intelligence and specifically deep learning. A review by Zaharchuk et al. in AJNR gives an in-depth explanation of the process by which deep learning can have useful applications in neuroradiology – but also provides hope that this will help rather than replace us!

That’s all for now, see you next month!

2017 Year in Review

Happy new year!

No full journal round-up this month, but I thought I would just do a brief summary of the year and highlight the most popular articles featured on the blog this year. There have been visitors from 40 countries over the last six months since its inception, and thank you to everyone who has fed back and particularly those who have contributed.

The top 5 articles (by click-through) from last year were:

Adams B et al. “Kinks and Clefts”: A Review of Congenital Brain Stem Abnormalities. Neurographics

An excellent overview of a complex topic – and gratifying that the most popular article this year was written by a UK trainee!

Johnson DR et al. 2016 Updates to the WHO Brain Tumour Classification System: What the Radiologist Needs to Know. Radiographics

The updated WHO classification, with particular emphasis on genetic factors, have dominated much of the neuro-oncology discussion this year so no surprises that this useful summary in Radiographics was a popular read.

Nguyen VD et al. Demystifying Orbital Emergencies. Radiographics

A comprehensive review of this often overlooked area, this is an excellent reference for orbital pathology.

Arnoux A et al. Imaging characteristics of venous parenchymal abnormalities. Stroke

This was a useful cohort review, which outlined the anatomical areas of abnormality related to the most common sites of venous occlusion.

Jansen O et al. Standards of Practice for Interventional Neuroradiology. Neuroradiology

With much of the year dominated by discussion of the utility of mechanical thrombectomy and how it will be implemented, this was a timely consensus statement for safe and effective use of interventional neuroradiology procedures.

Next year, we are looking forward to the BSNR Trainee Study Days on May 10-11th in Newcastle, and the BSNR Annual Meeting (and preceding study day) which is joint with the Irish Society of Neuroradiology and will be held in Dublin on 11-13th October 2018.

Hope you have an excellent 2018! See you next month.

November journal round-up

Welcome to the November round-up! There is a real wealth of interesting articles this month – these are my pick but do let us know what you have found useful.

Intervention – The big news this month was the reporting of the DAWN trial in the New England Journal of Medicine. The results had been eagerly awaited as it was strongly suspected that the timeframe for effectiveness of mechanical thrombectomy is longer than the traditional 6 hours, and sure enough there was significantly increased functional independence and reduced disability in the group that had a thrombectomy at 6 to 24 hours compared to the control group, with no significant difference in mortality or symptomatic haemorrhage. Importantly, the inclusion criteria specified demonstration of a mismatch between clinical severity and infarct volume as measured using CT perfusion or MRI DWI. This will obviously have major implications for organisation of stroke imaging and thrombectomy services.

Supportive evidence was also provided this month in the form of a subgroup analysis of the ESCAPE trial published in AJNR, which demonstrated a benefit for treatment within an extended time window (5.5-12 hours).

Vascular – Predicting progression of infarct is an important aspect of treatment and an article by Bouluois et al. in JAMA Neurol addresses a crucial issue, that if patients are transferred their infarct may progress beyond potential for treatment during the transfer. They assessed imaging factors associated with this progression in transferred patients, and found that collateral supply and clinical severity were key factors in determinants of infarct progression, suggesting a role for collateral assessment (they used a modified version of the Maas rating scale) in baseline stroke imaging.

Arnoux et al. in Stroke examined the imaging characteristics of the brain parenchyma related to cerebral venous thrombosis, looking at their own case series and identifying useful imaging features. They found that haemorrhagic ischaemia was the most common associated feature (followed by intracranial haemorrhage and non-haemorrhagic ischaemia), and determined six foci where parenchymal abnormalities occurred, with the inferior parietal lobule being the most common, and correlation between vessel and anatomical area.

Emergency – As everyone at RSNA this year will be acutely aware, artificial intelligence and deep learning are here to stay and an interesting article in Radiology by Prevedello et al. provides one example of how it may be used. They developed a system for identifying major abnormalities and showed good sensitivity and specificity for haemorrhage, mass effect and hydrocephalus (90% and 85% respectively) and reduced sensitivity but increased specificity for acute infarct (62% and 96%). This was for thick-section non contrast CT head, and the authors suggest this could help speed up workflow by highlighting critical cases to the radiologist.

Also in Radiology, Rodriguez-Luna et al. assessed the utility of the ‘spot sign’ to predict expansion of intracranial haemorrhage, and found that the use of multiphase CT angiography allowed greater stratification of risk with respect to the spot sign, with a more arterial ‘spot’ more predictive of haemorrhagic expansion.

Tumour – There is plenty to choose from this month, starting with a focused review on the aspects of the 2016 WHO classification of brain tumours relevant to radiologists in Radiographics. This is complemented by a more detailed review in Neurographics on the molecular subgroups of medulloblastoma described in the 2016 classification, covering specific imaging characteristics.

Also in Neurographics, Shin et al. provide an excellent overview of CNS lymphoma and its manifold presentations in immunocompetent and immunocompromised patients, with reference to advanced imaging techniques.

Finally, the humble vestibular schwannoma gets a whole review to itself in AJNR, covering diagnosis and imaging pathway but focusing on treatment options and follow-up, and is neatly accompanied by an article in JNS by Wu et al. specifically addressing post-Gamma Knife imaging appearances and predictors of treatment outcome.

Degenerative – The advent of susceptibility weighted imaging has led to an increase in the diagnosis of superficial siderosis, and an interesting study by Pichler et al. in Stroke investigated the prevalence in an elderly population. They found the incidence increased with age (0.21% at 50-69, 1.49% >69) and correlated with higher Apolipoprotein E e2 genotype and a higher likelihood of a positive amyloid PET, implicating cerebral amyloid angiopathy as the most common mechanism, and they therefore suggest follow-up imaging to assess risk of further haemorrhage.

The many different causes of dementia are covered in a comprehensive review by Desai et al. in Neurographics – the detailed table covering the imaging and clinical features of the different aetiologies is a particularly handy quick reference guide.

Paediatrics Adams et al. present an in-depth review of congenital brain stem abnormalities, and manage to make a complex topic admirably clear and practical, using the embryological and molecular underpinnings of the brain stem to classify the imaging phenotypes.

In Pediatric Radiology, Linscott et al. examine venous disease in children, covering the pathophysiology and the imaging features of acute and chronic venous injury.

Miscellaneous – An MDT can be a great opportunity to learn and share knowledge with fellow clinicians, or can be an opportunity for humiliation for an unsuspecting trainee. A survey by the JRF published in the BJR looks at the trainee experience of MDTs and subsequently provides a guide to approaching MDTs based on their findings. This can often be insufficiently covered in training and the article provides a good opportunity to think about training needs in this context, and is well worth a read.

That’s all for now, see you next month!

 

 

 

October Journal Round-Up

Welcome to the October journal round-up!

Vascular Mokin et al. tackle the issue of ASPECTS subjectivity in an interesting article in Stroke this month, using Hounsfield unit measurements (as a ratio and subtraction with the unaffected side) to provide a more objective measure and pave the way for automated image interpretation. This would hopefully standardise and speed up management decisions in thrombectomy, but requires validating in more extensive datasets.

Also considering automated assessments, Hanning et al. developed an automated segmentation and analysis of white matter lesion density on CT and showed a reasonable correlation with subsequent MRI white matter lesion load, which they felt may also lead to more rapid treatment decisions in acute stroke.

Baradaran et al. in AJNR performed a systematic review looking at high-risk features of carotid plaque on CTA, finding that the presence of soft plaque, plaque ulceration and increased carotid wall thickness correlated with ipsilateral ischaemia, whilst plaque calcification had a negative relationship with ischaemia.

Intervention – Two important studies in JNIS this month are again focused on thrombectomy. Frei et al. share their experience of using a standardized thrombectomy protocol (from pre-hospital to IR suite), and show a significant reduction in door to recanalization time. Alondo de Lecinana et al. describe the results of a prospective observational study showing that mechanical thrombectomy is safe and should be performed in patients with contraindication to intravenous thrombolysis.

Tumour – In Neurographics this month, there is a focus on glioma with reference to the 2016 WHO tumour classification (available here). A two-part review by Arevalo et al. in the first part gives an overview of basic tumour genetics covering significant mutations and the updated classification of gliomas, and in the second focuses on imaging features associated with the IDH mutant and wild type (see also the July blog and the review by Smits et al.).

Also with reference to the updated classification, a case series by Nunes et al. in AJNR examines the recently reported entity of a multinodular and vacuolating neuronal tumour, which is a ‘don’t touch’ lesion, and its imaging characteristics.

Inflammatory – Double inversion recovery remains a potentially powerful tool in MS imaging, and Eichinger and colleagues in AJNR have investigated a pre and post contrast and subtraction protocol to compare it to T1 weighted imaging. They demonstrate that DIR is more sensitive in detecting enhancing lesions, and suggest it as an alternative to T1 imaging.

Degenerative – Structural MRI can be of limited use in the setting of motor neuron disease, although volumetric MRI can demonstrate areas of parenchymal loss. Senda and colleagues looked at whether imaging characteristics (volume and DTI) could predict progression in motor neuron disease. They showed that atrophy and particularly grey matter loss, and a decrease in fractional anisotropy, in specific areas beyond just the corticospinal tract correlated with an increased rate of clinical disease progression.

Spine Cardenas et al. provide a useful and comprehensive pictorial review of pathologies of the conus medullaris and cauda equine in Neurographics, covering the spectrum of congenital, infectious/inflammatory, vascular, traumatic and neoplastic aetiologies.

Paediatrics – There is a focus on the rare Menkes disease in AJNR, with a two part review focusing on the vascular/white matter and grey matter changes in this progressive disorder. The authors compare their own case series with the literature for every imaging finding, which makes for a definitive review of this disorder although may be mainly relevant to specialist centres.

More common in everyday practice is the pineal cyst, and Jussila et al. followed up their cohort of pineal cysts in children and showed that the majority do not change, and suggest only re-imaging in the context of unusual radiological features or clinical symptoms.

Although we hope that it will not become necessary in the UK, there is a focused pictorial review in Radiographics this month demonstrating the pre- and postnatal imaging features of Zika virus in the brain covering sonographic and MR findings, and important differential diagnoses.

Miscellaneous – The debate about the use of gadolinium based contrast agents continues, and it is important as radiologists to be informed as to the mechanisms of action being uncovered. A useful review in BJR by the group that initially reported gadolinium deposition in the brain goes through our current knowledge of the mechanisms of gadolinium deposition, and in particular the role of the relatively newly-investigated glymphatic system.

And finally, just in case you wanted another differential for those nonspecific white matter lesions, in Neurology this month Alperin et al. discuss the findings of increased periventricular white matter lesions in returning astronauts. They do not say how often this history was mentioned in the clinical details.

That’s all for now – let us know what you’ve found useful this month!